They already do. Interdisciplinary is probably the biggest buzzword in academia today, architecture is designed to make people cross paths at the expense of inconvenicing them, etc. any good residental undergrad program has a strong coffee shop culture, debates in dorm common rooms long into the night, and inviting common spaces where faculty and students alike spend much of their time (though usually segregated by faculty/student and sometimes division).

I'd argue that in the US, no one does common spaces like a top-tier school.

One of the many reasons the residential nature of education matters and isn't obsoleted by MOOCs.